Photocatalytic Oxidation of NO2 on TiO2 : Evidence of a New Source of N2O5
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review
Author(s)
Related Research Unit(s)
Detail(s)
Original language | English |
---|---|
Article number | e202304017 |
Journal / Publication | Angewandte Chemie - International Edition |
Volume | 62 |
Issue number | 25 |
Online published | 14 Apr 2023 |
Publication status | Published - 19 Jun 2023 |
Link(s)
Abstract
N2O5 is an important intermediate in the atmospheric nitrogen cycle. Using a flow tube reactor, N2O5 was found to be released from the TiO2 surface during the photocatalytic oxidation of NO2, revealing a previously unreported source of N2O5. The rate of N2O5 release from TiO2 was dependent on the initial NO2 concentration, relative humidity, O2/N2 ratio, and irradiation intensity. Experimental evidence and quantum chemical calculations showed that NO2 can react with the surface hydroxyl groups and the generated electron holes on the TiO2, followed by combining with another NO2 molecule to form N2O5. The latter was physisorbed on TiO2 and had a low adsorption energy of −0.13 eV. Box model simulations indicated that the new source of N2O5 released from TiO2 can increase the daytime N2O5 concentration by up to 20 % in urban areas if abundant TiO2-containing materials and high NOx concentrations were present. This joint experimental/theoretical study not only demonstrates a new chemical mechanism for N2O5 formation but also has important implications for air quality in urban areas. © 2023 Wiley-VCH GmbH
Research Area(s)
- Atmospheric Chemistry, Heterogeneous Reactions, N2O5, NO2, TiO2
Citation Format(s)
In: Angewandte Chemie - International Edition, Vol. 62, No. 25, e202304017, 19.06.2023.
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review